Competent Cell prep

Dr. Klaus Eimert eimert at
Thu Apr 13 02:15:22 EST 2000

Imran Fatigue wrote:
> You should make sure that the ampicillin is fresh. Even if you are
> using freshly made up solutions of ampicillin, try to find out how old
> the solid ampicillin that you're using is. It's possible that over the
> years the ampicillin gets damp and then goes off.
> For a couple of years I used a mixture of methicillin and ampicillin to
> suppress satellite growth that had become an increasing problem. When
> eventually we bought fresh ampicillin, I found that the methicillin was
> no longer necessary.
> Sent via
> Before you buy.

Hi there,

we routinely replaced ampicillin with carbenicillin - much more stable,
longer "shelf time" of the plates, less satellites, reasonably priced.
Works great in our hands.

Hope that helps,


Dr. Klaus Eimert
Dept. of Botany
State Research Institute Geisenheim	Phone:    + 49 6722 502 469
Von-Lade-Str. 3				Fax:      + 49 6722 502 460
D-65366 Geisenheim			E-Mail:   eimert at
Germany					URL:

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